Combined set-square and bevel.



No. 642,566. Patented Ian. 30, I900. A. C. SMITH. COMBINED SET SQUARE AND BE VEL.

(Application filed Aug. 10,. 1899.)

(No Model.)

Raven/502 M aw-7% 0.. WASHINGTON n c UNTTED STATES ANDREIV C. SMITH, OF LOS ANGELES,

PATENT O FICE.

CALIFORNIA, ASSIGNOR TO THE LOS ANGELES AUTOMATIC TOOL COMPANY. I

SPECIFICATION forming part of Letters Patent No. 642,566, dated January 30, 1900.

Application filed August 10, 1899. serial No. 726,882. (No model.)

To aZZ whom it may concern.-

Beit known that I, ANDREW 0. SMITH, of the city of Los Angeles, county of Los Angeles, State of California, have invented certain new and useful Improvements in a Combined Set- Square and Bevel for Use by Carpenters, J oiners, and Others, of which the following is a full, clear, and exact description or specification, reference being had to the annexed sheet of drawings and to the letters marked thereon.

Myinvention, which relates to certain new and useful improvements in combined setsquares or bevels for use by carpenters and others, has for its object to enable the angles of joints in woodwork to be marked off exactly, so that the joined parts of woodwork may fit accurately to each other.

My new or improved instrument or device is to be used as a guide for marking pieces of timber whose ends have to be out to particular angles in wooden construction more especiallysuch, for example, as in or for the cutting of the ends of rafters used in framework of roofs or other analogous structures.

My invention consists of an adjustable instrument wherein there are two movable blades or straight-edges and a straight-edged stock. The blades or straight-edges are each carried upon a pivot, which pivot is situated near the upper end of the stock, at or near one side thereof, so that the two pivots are opposite to each other, and when the instrument is not in use both blades are folded into a slit in the stock, whereby they are inclosed and protected from injury. In each blade a circularly-curved slot is cut, whose centeris the center of the pivot of each blade, respectively, so that the curved slot in each blade, respectively, lies in opposite direction of curvature to that in the other blade when the blades are surperposed within the stock. The center lines of these curved slots intersect .each other, and at this point a set-bolt is passed through the stock and curved slots in the blades, having a pinching-nut upon the screwed outer end of the bolt for fastening the blades in any angular position in which they are set. In one of the blades an eccentrically-curved slot is out. A stud fastened in the other blade 50 projects into this eccentrically-curved slot, so

that the two blades being thus connected the movement of the blade in which is the eccentrically-curved slot, produces a movement of the other blade by reason of the eccentric slot in one blade operating upon the stud in the other blade, and according to the degree of eccentricity or variance of curvature of the eccentric slot so are the relative movement and position of the blades in respect of each other regulated, whence it follows that by using dilferent eccentricities or variationsof curvature of the eccentric slot so any required relationship or relative movement or angular position of the blades may be established.

My instrument or device as constructed for use in ordinary joiner or carpenter work has its eccentric curve so shaped that when one of the blades is set in a position of a square or at right angles to the stock the other blade is in a position of a half right angle or what is commonly called a miter. To facilitate the movement of the blades, the stud which operates in the eccentric curved slot is preferably mounted with an antifriction-roller.

On the annexed sheet of drawings, Figure 1 is a plan of my new or improved combined set-square or bevel. Fig. 2 is an edge or end elevation of the same. Fig. 3 is an enlarged view of the upper portion of my new setsquare or bevel drawn full size, showing the arrangement of the pivots and curves at the center and the eccentric curve.

My new and improved set-square or bevel consists of the stock A, which is preferably made of hard wood, such as rose-wood or similar material. At'its upper part this stock is mounted with the metallic cap-pieces B and B, respectively. A slit 0 equal to the thickness of the two blades of the instrument or device extends from the upper end of the 0 cap-pieces B B down to nearly the bottom of the stock A, as shown in the drawings. The two blades are respectively marked D and E, and they are preferably made of hard sheetsteel. The blades D E are pivoted to the 5 brass caps B of the stock A by pivotsF F, as shown, and in each of the blades D and E a curved slot G is cut, as shown at Fig. 3, which curved slot is struck from the center of the pivots F F. A pinching or set screw H passes through holes in the stock Aand through the slots G G. In the blade D the eccentric slot I is formed, and in the blade E a stud J is fixed. which projects up into the eccentric slot I of the blade D. This stud J is mounted with an antifriction-roller K, whose diameter is equal to the width of the eccentric slot I. From this construction of the device it will be seen that any movement imparted to the blade D by the hand of the carpenter, joiner, or other person using the same also imparts an angular movement to the blade E, this movement of the other blade E being brought about by reason of the eccentric slot I operating upon the stud J and the antifrictionroller K, carried by the blade E and projecting into the eccentric slot I.

In Fig. l the dotted position of the blade D in relation to the stock A is that of an ordinary try-square, and the corresponding position of the blade E, also shown dotted in Fig. 1, is that of a half right angle or miter, the eccentric slot I being so shaped that when the blade D is at right angles to the stock A the other blade E shall occupy the aforesaid position.

When it is desired that the blades D and E shall occupy some. other position than that shown by the dotted lines in Fig. 1, the blade D is moved upon its pivot and the eccentric slot I operates so as to move the other blade E into any required positionsuch, for example, as that shown in full lines in Figs. 1 and 3 of the drawings. The inner edge of the blade E is shown marked with inclined lines or a scale the position of which and the numbers on which indicate the relationship of the angle made by the blade E to that of the angle in which the blade D may be or is situated.

For the purpose of tightly holding the blades in whateverangular position they may be adjusted the bolt 11 is screwed at one end, and upon this end there is a pinching-nut L, as shown at Figs. 1 and 2, which when tightened by the thumb and finger pinches or holds the removable parts of the instrument or device in any fixed position.

Having now described the nature of my said invention and the best system, mode, or manner I am at present acquainted with for carrying the same into practical effect, I desire to observe in conclusion that what I consider to be novel and original, and therefore claim as the invention to be secured to me by Letters Patent, is as follows:

1. The new or improved combined adj ustable set-square or bevel in which there are two movable blades pivotally fastened into the stock of the instrument or device, one of these blades having in it an eccentric curved slot which operates upon a stud in the other blade so that when one of the blades is moved by the hand the other blade is operated relatively thereto into an altered position, dependent upon or corresponding with the cocentricity of the curved slot in the manner and for the purpose substantially as set forth.

2. The new or improved combined adjustable set-square or bevel in which there are two movable blades pivotally fastened into the stock of the instrument or device, one of these blades having in it an eccentric curved slot which operates upon a stud in the other blade so that when one of the blades is moved by the hands the other blade is operated relatively thereto into an altered position, dependent upon or corresponding with the cocentricity of the curved slot and provided with a pinching'screw passing through the stock and the regularly-curved slots, one in each blade, substantially as hereinbefore .described and contained upon the annexed drawings.

3. The new or improved combined adjustable set-square or bevel consisting of the stock, the pivoted blades, one of the blades having an eccentric slot therein, the other blade having a stud projecting into the said eccentric slot, both blades having curved slots struck from the center of the pivots of said blades, the set-screw with pinching-nut passing through the stock and through the regularly-curved slots in each blade all operating in the manner and for the purposes substantially'as set forth.

In testimony whereof I have hereunto set my hand and seal, in the presence of two subscribing witnesses, this 21st day of July, 1899.

ANDREW C. SMITH. IL. 8.]

lVitnesses:

ST. JOHN DAY, JOHN SA'ITERVVHIIE. 

